1. Field of the Invention
The present invention relates to a distributed type computer network for connecting and unifying a plurality of computer systems distributedly disposed through a communication medium.
2. Description of the Related Art
Recently, a distributed type computer network for allowing resources such as a file system and CPU to be shared with a plurality of computer systems (hereinafter named nodes) has gained public attention.
The distributed type computer network can advantageously share its resources with the nodes distributed in wide areas. However, as the network scale increases, the probability of illegal accesses also proportionally increases.
To prevent that, it is necessary to track a node and a path through which an illegal user accessed the network so as to improve the reliability thereof.
However, in most distributed type computer networks, at most the node just preceding the path through which the illegal user accessed the network can be tracked. Thus, to completely track the path through which the illegal user accessed the network, many complicated processes are required among all the related nodes and thereby much labor and time are disadvantageously used.